Pet brush



FIG. 1 is a perspective view of a pet brush showing by new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a side elevational view thereof;

FIG. 5 is a rear elevational view thereof; and,

FIG. 6 is a bottom plan view thereof.

The broken line structure shown in views is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a pet brush, substantially as shown and described. 